The brainchild of economics professor Phillip Levine, the quick college cost estimator tool is a variation of the net price calculators that schools participating in federal financial student aid programs had to post on their websites starting in late 2011. Those calculators show students the kind of aid package they could get, and how much school really would cost per year.

Officials at Wellesley said the school’s new free tool is meant to provide a quick cost estimate and doesn’t require families to dig up last year’s tax returns.

‘‘We want people to think that this is an option for them and investigate further. The whole point is we want the door to be open at the beginning,’’ Levine said Tuesday.

The economics professor said the tool was designed to take five minutes and asks a handful of financial questions that families can answer quickly, including total family income, home value and mortgage, non-retirement savings and cash in the bank. It also asks about the living situation of prospective students, because Levine said having divorced parents or siblings in college complicates the calculation.

While designed for Wellesley, whose alumni include former U.S. secretaries of state Madeleine Albright and Hillary Clinton, the professor said he believes the tool also could work for estimating costs at similar schools.

Levine said he created the tool using a formula that the College Board, the nonprofit that operates the SAT exam, uses for calculating financial need.

A Wellesley official will demonstrate it later this week at a guidance counselor convention in Toronto, and school officials are hoping its use will become widespread.

Diane Cheng, a research analyst at the nonprofit Institute for College Access and Success, said net price calculators that colleges use now have from about a dozen to several dozen questions. She said while a quick calculator tool wouldn’t offer a guarantee of what college would cost, it could help families.

‘‘Allowing students to answer a small amount of questions and get a quick ballpark estimate of their net price can be really helpful for them,’’ she said.